The medication under investigation at Saint Louis University – ancrod – will be given to patients within six hours of their stroke, which may double the time window when they can be treated. Those patients who can’t receive tPA may qualify for ancrod, which may be given longer after the onset of a stroke.
Ancrod reduces the amount of fibrinogen, a sticky protein that binds molecules together to form blood clots, in the body. Clots in blood vessels block the flow of blood into the brain and cause ischemic strokes. Researchers are testing the medication derived from the venom of the Malayan pit viper because it specifically attacks fibrinogen.
“Reducing the fibrinogen in the blood reduces clot formation and also improves blood flow within and to the brain,” says Salvador Cruz-Flores, M.D., associate professor of neurology at Saint Louis University and the principal researcher for the study. “Some evidence suggests that ancrod’s action on fibrinogen also may prevent stroke-causing clots from extending and indirectly may help destroy them. By stopping clot formation and destroying clots that already have formed, we hope to improve the blood flow to the part of the brain suffering a stroke. The idea is to protect the brain tissue and limit injury and disability.”
Saint Louis University is recruiting six stroke patients at Saint Louis University Hospital to participate in the clinical trial. Half will receive an intravenous infusion of ancrod and half will receive a placebo. Both groups will otherwise receive the same standard of care. Both groups of patients will be followed for 90 days; then researchers will compare how well they function in daily activities. A total of 650 participants are being recruited worldwide.
Stroke is the third-leading cause of death and leading cause of disability in the US.